Fix Figma Weave SDK failed to initialize error

If you are trying to embed or integrate Figma Weave into your web application and see "SDK failed to initialize", "Weave is not defined", or unhandled promise rejections during startup, the SDK is failing to establish a secure handshake with Figma’s API.

This issue usually stems from misconfigured API keys, environment variable mismatches, restrictive Content Security Policies (CSP), or version conflicts within your package manager.

Follow these step-by-step troubleshooting instructions to identify and resolve the initialization block.

1. Verify Your API Key and Environment Variables

The most common cause of initialization failure is a malformed, expired, or missing API key. When the SDK loads, it immediately validates the key against Figma's developer gateway.

1. Check variable prefixing: If you are using React, Vite, or Next.js, ensure your environment variables are correctly prefixed for your framework. For example: * Next.js: NEXT_PUBLIC_FIGMA_WEAVE_KEY * Vite: VITE_FIGMA_WEAVE_KEY * Create React App: REACT_APP_FIGMA_WEAVE_KEY 2. Avoid hardcoding: Never hardcode keys directly into your client-side code. If you must do so for temporary local testing, ensure the key is wrapped in quotes and has no trailing spaces. 3. Test key validity manually: Run a quick cURL command in your terminal to see if the key is still active and valid: `bash curl -H "Authorization: Bearer YOUR_API_KEY" https://api.figma.com/v1/me ` If this returns a 401 Unauthorized or 403 Forbidden error, generate a new token from your Figma Developer Settings.

2. Configure Content Security Policy (CSP) Headers

Modern browsers will block the Figma Weave SDK from loading external iframe assets or communicating with the parent window if your site's Content Security Policy (CSP) is too restrictive.

1. Open your browser's Developer Tools (F12) and check the Console tab for CSP violation errors. 2. If you see errors containing Refused to load the script... because it violates the following Content Security Policy directive, you must update your CSP headers. 3. Add the following directives to your server configuration or HTML <meta> tag to permit communication with Figma's CDN and APIs: `http Content-Security-Policy: default-src 'self'; script-src 'self' https://*.figma.com; frame-src 'self' https://*.figma.com; connect-src 'self' https://*.figma.com; ` 4. Save the configuration and force-refresh your browser (Ctrl + F5 or Cmd + Shift + R) to bypass cached CSP rules.

3. Resolve Dependency Conflicts and SDK Version Mismatches

If you installed the SDK via npm or yarn, mismatched dependencies or a corrupted cache can prevent the bundle from building or loading correctly in the browser.

1. Check your package version: Open your project's package.json file and locate @figma/weave (or the corresponding SDK package name). Ensure you are running the latest stable version. 2. Clean install dependencies: Run the following commands to clear build caches and reinstall fresh packages: `bash # For npm users rm -rf node_modules package-lock.json npm cache clean --force npm install

For Yarn users rm -rf node_modules yarn.lock yarn cache clean yarn install ``` 3. **Check for duplicate installations:** Ensure your build tool (Webpack, Vite, or Rollup) is not bundling multiple versions of the SDK, which can cause internal namespace conflicts.

4. Debug Cross-Origin Resource Sharing (CORS) and Network Blocks

Sometimes, local security tools, VPNs, or browser extensions block the SDK's initialization requests to Figma's servers.

1. Inspect the Network tab: Filter for weave or figma.com in your browser's Network panel. Look for failed preflight (OPTIONS) requests or blocked calls showing CORS error or Failed to load resource.
2. Disable browser extensions: Adblockers, privacy shields, and tracking blockers often flag design collaboration SDKs as third-party trackers. Test your application in an incognito/private window with all browser extensions completely disabled.
3. Configure local proxy (if applicable): If you are developing behind a strict corporate firewall, configure your local development server to proxy requests to https://api.figma.com to bypass CORS limitations.

When to Escalate

If the SDK still fails to initialize after verifying your keys, updating dependencies, and confirming your CSP rules allow connections to Figma, check the Figma Status Page to verify there are no active API outages.

If services are operational, collect your browser's console logs, network HAR export files, and your current SDK integration code snippet (redacting any private tokens) and open a ticket through the Figma Developer Forum or contact your enterprise support representative.